MELBOURNE, Fla. (AP)  A union representing 570 space shuttle program workers at the Kennedy Space Center voted to strike Saturday, less than a week before the planned launch of the shuttle Atlantis.

The International Association of Machinist and Aerospace Workers, which represents the United Space Alliance employees, rejected the company's contract offer Saturday morning, Florida Today reported.

United Space Alliance spokeswoman Tracy Yates said the union could strike as early as June 10, two days after NASA officials plan to launch Atlantis.

"The bottom line is, a strike would not affect the next launch or the next one after that," Yates said. The company "has a plan in place."

The union's negotiating team felt the company's offer was "substandard," said Lynn Beattie, a member of the group and former Local 2061 president. Both sides have agreed to a five-day cooling off period.

United Space Alliance remains hopeful that an agreement will be reached before a strike but stands by the company's negotiations, Yates said.

"We believe our offer was fair, competitive and responsive to the issues that were raised during the negotiation," she said.

A call to the International Association of Machinist and Aerospace Workers was not returned Saturday.

Copyright 2007 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.